All hard drives crash eventually. Even with the advancements in technology, hard drives in our computers will eventually fail. Might happen with the first 2-3 years or even after 5+ years. But if we practice a few simple rules there should be no reason to lose your data entirely.
Hourly timed backups. If you own an Apple computer with a recent operating system, you can use Time Machine which you can set to backup your computer regularly or per hour. On a windows machine you can do something similar and all you will need is a good USB external hard drive.
Complete backup of your hard drive is another option. You can purchase an additional hard drive and backup a complete copy so if there is a hard drive failure, you have a complete clone or copy. This is not done hourly but more of a weekly occurrence.
Another option is the online backup. Products such as carbonite, mozy, etc. are online versions of backing up your hard drive and they do vary on cost.
And finally all three are good options. If you really want to keep a complete backup of your important files use the first three options and you should be very secure.
Make the the first hard drive fail be your last and make sure you regularly backup your computer.